As described in applicant's U.S. Pat. No. 9,135,897 for a “Magnetic Guitar Pick Ring and Material for Use Therewith,” a plastic guitar pick with magnetic properties that can retract back to a ring worn on the finger of a strumming hand was developed. In certain embodiments, the plastic could have BaFe nanoparticles infused inside it. U.S. Pat. No. 9,135,897 is hereby incorporated by reference in its entirety.
The process for creating the plastic having magnetic properties according to the prior art is called “Injection Molded Magnets.” The process involves embedding two magnets into the injection machine tool mold by machining in the magnets, which is a very expensive and time consuming process. There is one magnet with a north pole and one magnet with a south pole in each side of the mold, thus creating a magnetic field. However, the early production of “Injection Molded Magnets” consisted of hard, dense, and heavy resins and polymers. They needed to use large ratios of strontium ferrite (SrFe) and BaFe to make the material magnetic, thus making the resulting material brittle and heavy. An analysis of the material indicates that carbon and many types of metals are present in varying concentrations, including boron (84 mg/Kg of the material), barium (442 mg/Kg), iron (151,000 mg/Kg), titanium (49 mg/Kg) and strontium (30,200 mg/Kg). However, this material also contains a significant amount of other filler materials. The uses for these “magnetic polymers” are limited to internal mechanical components, and have very few uses in the mainstream marketplace.
FIG. 1 shows a sample product made using the “injection molded magnets” method according to the prior art. FIG. 1 shows coupling pieces, including a smaller piece that fits inside a larger housing piece and is attached magnetically to the larger housing. If one moves the smaller piece inside the magnetic resistance can be felt. However, these pieces are quite heavy, dense and brittle, and are not very “plastic” like.
Additionally, the extrusion process of making nano-infused plastic pellets for injection machines was infrequently conducted in the United States because the components or the custom metallic alloy particles like BaFe used in the injection process were exclusively produced in Asia. The process was too expensive, and that is why it was basically abandoned, and then subsequently became an underdeveloped technology.